Mar., 1904.] 
Extra-Floral Nectaries and Glands. 
103 
Aradus ornatus Say. Collected bj- Mr. Dury at Cincinnati. This is an 
especially interesting addition to our list as the species has been un- 
known since Say’s description in 1831, until a few years ago when 
Bergroth rediscovered it. I have noted it in the Ohio Naturalist, volume 
IV, page 22. 
Aradus Duryi Osb. Cincinnati, collected by Mr. Dury. 
Aradus Duzei Bergroth. Westerville, J. G. Sanders. Cincinnati (Dury). 
Brachyrhynchus lobatus Say. Cincinnati by Mr. Dury. 
Neuroctenus elongatus Osb. Cincinnati (Durv). 
Neuroctenus ovatus Stal. Cincinnati (Dury). Two species. Previoush- 
recorded for Mexico and North Carolina. 
Coriscus propinquus Rent. Columbus. 
Opsicoetus personatus L. Has been rather frequent in Columbus and 
Sandusky. 
Pelogonus americanus Uh. Cedar point. Sandusky. 
Limnoporus rufoscutellatus Lat. Cedar Point. 
OHIO PLANTS WITH EXTRA-FLORAL NECTARIES 
AND OTHER GLANDS.* 
John H. Sch.\ffner. 
The existence of glands and nectaries outside of the flower or 
inflorescence has been a subject of much interest to biologists. 
Delpino, Darwin, Trelease, and many others have given a large 
amount of information in regard to the occurence and nature of 
these organs ; yet much is still obscure and any one so inclined 
ma}’ at least obtain considerable pleasure b}’ making observations 
along this line. 
A'arious views have been held as to the cause and use of extra- 
floral glands and their secretions. Delpino considered that the 
power to secrete nectar b\- an}- extra-floral organ has been speci- 
ally gained in every case for the sake of attracting ants and 
wasps as a body-guard, or as defenders of the plant against enemies. 
Darwin while admitting that this may be the case in some plants 
did not think that all such glands originated in this way. He 
held that the saccharine matter in nectar was excreted as a waste 
product of chemical changes in the sap and that this product 
might then become useful for accomplishing cross-fertilization or 
for attracting a body-guard, and thus the nectary would become 
an object for selection. He cites the case of the leaves of certain 
trees where a saccharine fluid, often called honey-dew, is excreted 
without the aid of special glands. By some, the special use of 
extra-floral nectar is supposed to be to divert ants and other 
insects from visiting flowers which they might otherwise injure. 
But many plants have nectar long before and long after the 
flowering period. On Viburnum opulus, for example, nectar is 
still present and abundantly used by ants late in October. An- 
other view has been that certain of the.se glands act as absorptive 
’^Read at the ISIeetiiig of the Ohio State Academy of Science. 
